Rotary engine.



No. 761,095. PATENTED MAY 31, 1904.

- T. W. NORDENFELT.

ROTARY ENGINE. APPLICATION-FILED- JULY-11, 1903 N0 MODEL. n 4 SHEETS-SHEET 1.

7. M MW MM 2% W No. 761,095. PATENTBD MAY 31; 1904.

" T. W. NORDENFELT.

ROTARY ENGINE.

APPLICATION FILED JULY 1;, 1903. no MODEL. 4 SHEETS-SHEET 2.

v 761,095" PATENTBD MAY 31-, 1904.

T. W. NORDENFELT.

ROTARY ENGINE APPLIOATION FILED JULY 11, 1903.

N0 MODEL. 4 SHEETS-SHEET 3.

Wi f 76 A 76' Z w, W

No. 761,095. PATENTED MAY 31,1904.

1?. W. NORDENFELT.

ROTARY ENGINE. APPLICATION 111.111) JULY 11, 1903.

' 4 SHEETS-SHEET 4.

110 MQD'EL.

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Patented May 31, 19:44.

PATENT OFFICE.

ROTARY ENGINE.

SPECIFICATION forming part of Letters Patent NO. 761,095, dated May 31, 1904.

Application filed July 11, 1903. Serial N0 165,140. (No model.)

trically to the piston that the piston forms a steam-tight joint where it is in close contact with the inner surface of the cylinder, so that they both revolve together.

The ob ect of my invention is to make such engines more economical in the consumption of steam or other driving fluids, more dura-z ble, and of lncreased efficiency or power.

In order to increase the power or to reduce the consumption of steam for equal power,

two (or more) pistons, each provided with its own sliding shutters, are fixed on one shaft .and work in one cylinder, with a partition between the pistons, so that steam is prevented from passing directly from one compartment to the other. The steam enters a hollow shaft at one end and passes through the first piston into the high-pressure compartment. When the work of its pressure and expansion in that compartment has been, accomplished in the manner usual in this class of rotary engines, the steam passes at reduced pressure into an eccentric annular space formed by the partition between the pistons and the shaft, then either through a passage cast in the second piston or directly into the hollow shaft, but into a compartment of it separate from that into which it was first admitted, this compartment of the hollow shaft, together with the eccentric annular space, and sometimes the passage in the second piston, acting together as a receiver for the steam arriving from the high-pressure compartment. The steam then passes through the second piston into the low-pressure compartment, which is or against its lining-tube.

more spacious'and preferably longer than the first. It then again works by pressure and expansion, and so on until it is finally exhausted into the open air or into a condenser, as may be desired. I inclose the cylinder in a casing with side walls reaching so far inward as to touch the collars of the cylinder inside the cylinder-bearings and with packing at the joints. The space so formed between the cylinder and the frame can be used as a steam-jacket for keeping the outside of the cylinder hot by means of steam taken out of the supply-pipe from the boiler.

The admission and distribution of steam can be effected through a fixed tube within the hollow shaft, into which the tube is inserted so far that its steam-port is opposite the channels in the piston through which the steam passes into the cylinder-space. I

In order to prevent any loss of steam by leakage around such fixed distributing-tube or past its ends, 1 place along the fixed tube at the sides of the steam-port packing-slides pushed outward by springs, slightly compressed into the fixed tube when this is pushed into the hollow shaft, so that the slides bear tightly against the inner surface of the shaft I also place packing-rings with springs round the fixed tube beyond the ends of the steam-port or at the ends of the fixed tube.

When it is important to reduce the clearance to a minimum, I do not use a fixed distributing-tube with a' steam-port opposite the ad' to and fro by a lever rocked on a pin with bearings in the piston or in the shaft by a cam-groove on a fixed rod or tube within and around which the steam passes, and I use a spring for closing the valve rapidly. The

two faces of the valve-plunger upon which the lever acts are of equal size, so that the valve is equilibrated and acts independently of 2 suitable pressure can be easily obtained be- In compound engines, as well as in singlethe steam-pressure.

cylinder engines, I can use for steam distribution either a central fixed tube or a valve independent of centrifugal force for both the high and the low pressurecompartments or one of these means of distribution for the hi ghpressure and the other for the low-pressure;

compartment.

The durability of an engine depends greatly upon the lubrication of the parts, and in order to improve this I prefer to grease the surfaces exposed to friction by fluid oil instead of introducing oil into the steam and letting the steam carry the'oil to the wearing-surfaces,

which has been found detrimental to the conv densers and to the boiler-tubes.

When I use a fixed distributing-tube, I lubricate the engine by forcing theoil through a channel which I bore lengthwise'througlr thewa'll of the tube. From this channel oil passes to the packing slides and rings and by centrifugal force through channels in the pis-.

ton to oil-passages on the face of the slots in.

which the sliding shutters move and to the .end

faces of thepiston. V

When distributing-valves are used instead of the fixed tube, I have no packing slides or rings to lubricate, and I then lead theoil through a pipe passing through the crescentshaped space between the cylinder-collar and the shaft to an annular groove cut in the end I face of the piston, whence the oi'l'is driven by ton only when it isto escape through the crescent-shaped opening between'the cylindercollar and the shaft at the end of the piston, and it is led away clear of the cylinder-casing. A governor and throttle-Valve are provided for suitably regulating the speed ofthe engine and can be adjusted for various speeds without stopping the engine by compressing a spring acting on the valve by means of a screw-cap.

The bearings for the shaft and cylinder can be of any suitable form, preferably rollerbearings with cages to keep the rollers in position, so as to diminish their friction, or in order to make the engine run more steadily, especially when the power is taken by a belt from a pulley on the shaft, I can use ring-bearings running in oil-baths for the shaft and roller bearings inside the engine-frame only for the bearings of the cylinder-collars. In this case the oil used for the shaft-bearings of admission and exhaust.

will not come into contact with the steam. The shaft-bearings or the cylinder-bearings are ad ustable in any usual manner, so that a tween the piston and the cylinder at their line of contact.

The channels for the inlet and exhaust are placed at such angles. as are convenient for the-number of sliding shutters used in order to give the most suitable periods of inlet and exhaust; of the steam.

The adjustment of the contact between the ends of the piston and of the cylinder can be effected by means of an adjustment disk and wedges acted upon by screws, as has previously been done in this class of engines.

My invention is illustrated by the drawings annexed.

Figure 1 shows a longitudinal section of a- 5 compound engineinwhich a fixed tube is used to both pistons, the shutters and. the channels for admission and exhaust being shown in such a manner as to make them easily under stood; but in manufacturing these have to be put at such angles as are necessitated by the number of shutters (two ormore) that are used and'so as to determinethe desired periods Fig. 1 shows the governor with its gearing for controlling the admission of steamto the engine. Fig. 2

is an end view of the pistons of a compound ofthe pistons shown in Fig. 2., Fig. 4: is a View similar to Fig. 1, but with the low-pressure piston fitted with a balanced valve, such as de scribed. I Fig. .5 is a longitudinal section (through the slot in which the sliding-shutter moves) ofalow-pressure piston for fixeddistributing -tube, showing the arrangement for lubrication by fluid oil. Fig. 6 is a cross- ,section, to a larger scale, of the fixed distributing-tube with packing-slides and oil-channel. Fig. 7 is a half longitudinal section of the details shown in Fig. 6.

1 is the shaft, having fast on it high and low pressure pistons 2 3, fitted with. sliding shutters 4.

' 5 is the cylinder, with collars 6, supported in bearings 7 carried by the casing 8, whose in order'to prevent loss 'of heat by radiation Y from the cylinder, while the casing and cylinders areproteeted by lagging 14.

i 15 is the adjustment-disk for adjusting th contact between the ends of the piston and the cylinder, and 16 is the partition dividing the cylinder into two compartments.

Suitablepacking 12 is provided to ren- 5 for the admission-and,distributionofsteam The shaft 1 may be fitted with a liner 17 within which is the fixedtube 18 with high and ,low pressure admission-ports 19 and 20.

' also be employed. Steam passes from the interior of the tube 18, through port 19, to passages 24 in the piston 2 to the high-pressure compartment and having done its Work there through passages 25 in the piston 2 to thespace 26 between the shaft and the partition 16, thence by passages 27 in the piston 3 to the interior of the tube 18 on the far side of a diaphragm 28, the passages 25 and 27, the space 26, and the interior of the tube all acting as a.

Thence the steam passes, by port receiver. 20 and passages 29 in the piston 3, to the lowpressure compartment, from which it exhausts by passages 30 in the piston to the crescent-shaped space 31 and exhaust-pipe 32.

The tube 18 is carried by an end framing 33, in which is the steam-inlet pipe 34 and a governor 35, driven from the shaft by gearwheels 36.

This governor controls a balanced throttle-valve 37 in the inlet-pipe.

, Though the engine shown is only a compound engine, it will be obvious that the "engine may be adapted to multiple expansion by having more than one partition in the cylin- .der and a corresponding number of pistons on the shaft.

In place of the distribution-tubelS I may admit steam to the interior of the piston, from which it passes to the cylinder by way of j valves 38, (shown in Fig. 4,) one valve being provided for each shutter. Each valve is arranged so that it shall move parallel to the shaft and shall thus be independent of centrifugal action. It is normally kept up against its seating by a spring 39 and is operated at the proper time by a lever 40, pivoted in the piston or shaft, the tail of this lever being operated by a cam 41 on a fixed tube or rod 42.

In the case of compound engines the fixedtube method may be employed for both cylinders, as illustrated in' Fig. 1, or thefixed tube may be used for the highpressure cylinder and valves 38 for the low-pressure, as illustrated in Fig. 4, or, again, valves may be employed for both.

The lubricating arrangement is seen in Figs.

5 and 6. Oil may be forced through a longitudinal channel 43 in the tube 18, whence it passes by centrifugal action to passages 44 in the piston and grooves 45 in the shutters.

What I claim is 1. In a rotary engine the combination of a rotating cylinder, bearings therefor, a rotating shaft eccentric to the cylinder, bearings for the shaft, a partition dividing the cylinder into two chambers, a pair of pistons fast with the shaft and adapted tomove one in each chamber, shutters sliding in the pistons, means for admitting motive fluid to the high-pressure .pressure chamber.

chamber, means for allowing the fluid to pass from the high-pressure to the low-pressure chamber, and means for allowing the fluid to escapefrom the low-pressure chamber.

2. In a rotary engine the combination of a rotating cylinder, bearings therefor, a casing surrounding the same, a rotating shaft eccentric to the cylinder, bearings for the shaft, a partition dividing the cylinder into two chambers, a pair of pistons fast with the shaft and adapted to move one in each chamber, shutters sliding in the pistons, means for admitting motive fluid to the high-pressure chamber, means for allowing the fluid to pass from the high-pressure to the low-pressure chamber, and means for allowing the fluid to escape from the low-pressure chamber through the crescent-shaped space between the shaft and the cylinder and an exhaust-pipe outside the casing.

3. .In a rotary engine the combination of a rotating cylinder, bearings therefor, a hollow rotating shaft eccentric tothe cylinder, bearings for the shaft, apartition dividing the cylinder into two chambers, a pair of pistons fast with the shaft and adapted to move one in each chamber, shutters sliding in the pistons,

a fixed tube within the'shaft admitting motive fluid to the high-pressure chamber, means for allowing the fluid to pass from the high-pressure to the low-pressure chamber, and means for allowingthe fluid to escape from the low- 4. In a rotary engine, the combination of a rotating cylinder, bearings therefor, a hollow rotating shaft eccentric to the cylinder, bearings for the shaft, a partition dividing the cylinder into two chambers, a pair of pistons fast with the shaft and adapted to move one in each chamber, shutters sliding in the pistons, a fixed tube within the shaft and having a port in it registering with passages in the piston for admitting motive fluid to the highpressure chamber, stationary packing carried by the tube around the port, means for allowing the fluid to pass from the high-pressure to the low-pressure chamber, and means for allowing the fluid to escape from the low-pressure chamber.

5. In a rotary engine the combination of a rotating cylinder, bearings therefor, a hollow rotating shaft eccentric to the cylinder, bearings for the shaft, a partition dividing the cylinder into two chambers, a pair of pistons fast with the shaft and adapted to move one in each chamber, shutters sliding in the pistons, a fixed tube within the shaft admitting motive fluid to the high-pressure chamber, means for allowing the fluid to pass from the high-pressure chamber to the crescent-shaped space between the partition and the shaft and to the interior of the tube and shaft, means for allowing it to pass thence to the low-pressure chamber, and means for allowing the fluid to escape from the low-pressure chamber.

6. In a rotary engine the combination of a rotating cylinder, bearings therefor, a hollow rotating shaft eccentric to the cylinder, bearings for the shaft, a partition dividing the cylinder into two chambers, a pair of pistons fast with the shaft and adapted to move one in each chamber, shutters sliding in the pistons, a fixed tube within the shaft admitting motive fluid to the high-pressure chamber, means for allowing the fluid to pass from the high-pressure to the low-pressure chamber, means for allowing the fluid to escape from the low-pressure chamber, a longitudinal oilchannel in the fixed tube and oil-grooves in the pistons and shutters communicating with the channel.

7 In a rotary engine the combination of a rotating cylinder, bearings therefor, a hollow rotating shaft eccentric to the cylinder, bearings for the shaft, a partition dividing the cylinder into two chambers, a pair of pistons fast with the shaft and adapted to move one in each chamber, shutters slidingin the pistons, a fixed tube within the shaft, a diaphragm in the tube, a port on the admission side of the diaphragm registering with passages in the high-pressure piston for admitting motive fluid to the high-pressure chamber, means for allowing the fluid to pass from the highpressure chamber to the interior of the tube beyond the diaphragm, a second port in the tube beyond the diaphragm registering with passages in the low-pressure cylinder, and means for allowing the fluid to escape from the low-pressure chamber.

8. In a rotary engine the combination of a rotating cylinder, bearings therefor, a hollow rotating shaft eccentric to the cylinder, bearings for the shaft, a partition dividing the cylinder into two chambers, a pair of pistons fast low-pressure piston leading to the low-pressure chamber, a valve in each passage adapted to move parallel to the shaft, and means for operating the valve.

9. In a rotary engine, the combination of a cylinder, a piston, a shaft, a lift-valve in the piston adapted to move parallel with the axis of the shaft, and means for thus moving the valve during each revolution of the piston to open and close the admission-port ofthe cylinder.

10. In a rotary engine the combination of a lift-valve in the piston adapted to move parallel to the axis of the shaft, a spring tending to keep the valve closed, a lever pivoted in the piston, and means for rocking the lever to open the valve.

11. In a rotary engine the combination of a lift-Valve in the piston adapted to move parallel to the axis of the shaft, a spring tending to keep the valve closed, a fixed cam-surface within the shaft, and a pivoted lever bearing against the cam-surface and adapted to open the valve.

THORSTEN WILHELM NORDENFELT.

Witnesses:

GEORGE I. BRIDGES, ROBERT B. RANsFoRD. 

